Objective

The project develops and demonstrates nearly Zero Energy Wood Buildings design process and procurement models with reduced cost for large-scale use in the northern climatic conditions and on performance level of nearly zero and beyond. The project promotes large-scale market uptake of the developed nearly Zero Energy Wood Building applicable for construction industry design and procurement process. On site and nearby renewable energy system solutions are studied in order to provide real addition of renewable and energy production of on-site energy system. In addition to the nearly zero energy performance level, the project is also focusing on the performance level, which does beyond the nZEB level. Demonstration tasks on net-zero and energy-plus level will be also executed in the project. Analysis of the technical solutions including renewable energy systems will also reach to the plus-energy level because several nZEB buildings studied in the project will be plus-energy buildings.

The project develops and demonstrates methods and solutions, which significantly reduce the cost of new nearly Zero Energy Wood Buildings compared to the current situation. The project develops standard design process and procurement models for cost reduction for different building types for the Northern Europe climatic conditions. The cost reduction of the nearly Zero Energy Wood Buildings is shown in the project by means of the demonstration projects including both residential and non-residential single buildings. Wood buildings can result in 50 % reduced GHG emissions compared to conventional buildings with steel and concrete structures.

Periodic Reporting for period 1 - NERO (Cost reduction of new Nearly Zero-Energy Wooden buildings in the Northern Climatic Conditions)

NERO project works with cost reduction of wooden nearly zero energy buildings in a cold climate. In such a severe climate, heating is clearly dominating and the construction cost of heavily insulated nearly zero energy buildings is an evident challenge. The project aims to collected data from 11 existing case buildings representing educational and residential multifamily buildings and to conduct more detailed construction cost breakdown and life cycle costs analyses for 6 demonstration buildings including also NZEB districts. t is highly important to study new highly performing buildings with advanced technical solutions in order to be sure that such buildings can provide healthy and comfortable indoor climate together with superior energy performance at reasonable construction cost. Both good and bad experiences are highly valuable to be reported and disseminated in the fashion that decision makers and construction professionals receive information making it possible to procure and construct safely and successfully such buildings with heavily changed technical solutions. This is the main mission of NERO, to collect and identify best practices and robust solutions with proven performance, and to report this information in enough detailed format, so that construction professionals can utilize and apply these solutions in future projects. Prefabrication in controlled factory conditions, fast construction time as well as the integration of HVAC systems and insulation in load bearing structural elements are some keywords enabling cost reduction together with optimized design boosted by dynamic energy simulation methods widely in use in Nordic countries.

NERO collected construction cost and operational energy data from 11 case buildings. Metered energy data was studied against monitored indoor climate – the ventilation and thermal comfort and occupant satisfactory questionnaire in order to be sure that energy performance targets of NZEB buildings have been achieved without compromising indoor climate and occupant comfort. The results showed that in many buildings either indoor climate or energy targets were not met in practice, and only in minority of buildings these targets were achieved simultaneously. NERO demonstration project analyses are in progress including construction cost and life cycle cost analyses and identification of cost-effective solutions and measures.

NERO data collection and monitoring in new NZEBs has revealed many unexpected risks and performance gaps both in energy use and indoor climate. Collected evidence on problems and also from well-functioning solutions and buildings helps to identify critical aspects and steps both in design, construction and operation and maintenance, and generally to avoid drawbacks in highly performing buildings in future. NERO demonstration projects ongoing analyses are expected to show evidence and good practices enabling to achieve reasonable construction cost and to reduce life cycle cost and carbon footprint of NZEB buildings.